Age at natural menopause and the risk of epithelial ovarian cancer

Objective: To investigate the relationship between age at natural menopause and risk of developing epithelial ovarian cancer. Methods: Using data from six population-based, case-control studies conducted in the United States, age at natural menopause among 1411 women with epithelial ovarian cancer and 6380 control subjects were analyzed using survival analysis methods, including Kaplan-Meier and proportional hazards models. Subjects ranged from 20 to 81 years of age. Results: The median age at natural menopause was 50 years among cases compared with 51 years among controls, a difference of borderline statistical significance (P = .06). The hazard ratio for the relationship between case-control status and age at natural menopause was 1.09 (95% confidence interval 0.99, 1.20). Controlling for potential confounders including parity, oral contraceptive use, tubal ligation, smoking, and body mass index did not appreciably change this association. There was little evidence of an association between early age at natural menopause and early onset ovarian cancer (diagnosis age under 48 years). Conclusion: We observed a weak association between ovarian cancer risk and age at natural menopause and, among women with early onset disease, there was little evidence to suggest that early menopause is related to ovarian cancer. Thus, there seems little need for increased surveillance or screening for ovarian cancer among women with early natural menopause.